Singularity Analysis for Articulated Object Tracking

Daniel D. Morris
Robotics Institute
Carnegie Mellon University
Pittsburgh, PA 15213
James M. Rehg
Cambridge Research Lab
Compaq Computer Corporation
Cambridge, MA 02139


This project consists of work I did with Jim Rehg at Compaq's Cambridge Research Lab (formerly Digital Equipment Coporation) in the summer of 1997. We extend Jim's thesis work at CMU on visual tracking of a hand to more general articulated figures.

We analyze the use of kinematic constraints for articulated object tracking. Conditions for the occurrence of singularities in 3-D models are presented and their effects on tracking are characterized. We describe a novel 2-D Scaled Prismatic Model (SPM) for figure registration. In contrast to 3-D kinematic models, the SPM has fewer singularity problems and does not require detailed knowledge of the 3-D kinematics. We fully characterize the singularities in the SPM and illustrate tracking through singularities using synthetic and real examples with 3-D and 2-D models. Our results demonstrate the significant benefits of the SPM in tracking with a single source of video.

Full compressed postscript file (660K)

Appeared in: CVPR '98, Santa Barbara, CA, June 1998.

See also Technical Report at Compaq.

Video Demos:

Fred Astaire Dancing

Tracking using SPM

Fred in my office

Bill and Ginger

Last modified: Wed May 26 10:36:48 EDT 1999

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